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shelocta · 10-09-2012, 12:31 AM

MegaShift™ Transmission Controller is somewhat like a Heath kit that you can get completely built. One of its defaults is the 4L80E and I just glanced through their documentation but if you can build the kit correctly it doesn't seem very hard to implement. If my TH400 blows up I think I would be tempted to go this route but I believe you would have to build a spare, unless you can figure out a limp home mode. If nothing else their site has a lot of good information on transmission controllers and is well worth browsing.
The link to the site is MegaShift/GPIO Transmission Controller
Bill

LimeyRich · 10-09-2012, 11:02 AM

bkahler .Just a quick thought before I leave the house. Before you remove the drive shaft from the Argosy you must mark its exact position in the vertical plane. I used the 3/8" inch nut on a string method, run a string (with a nut attached) over a floor brace, suspend the nut so that it is just grazing the top of the driveshaft. Secure the string so that it cannot slip. Now you have the exact position of the driveshaft, and can install the newly shortened shaft just grazing the nut, and your geometry is unchanged. This is very important if you do not want to destroy multiple U-joints. Shim the transmission mount to get the geometry exact. Got to go .
All the best.
P.S. Thanks for the pic Keyair, yup 345 brake there, like the long tube headers. Hopefully I can get my camera working soon.

ElCamino Man · 10-09-2012, 03:47 PM

Wow that E-Brake looks identical to a regular E-Brake lol.

And cutting the frame is ok on a scrap frame lol

LimeyRich · 10-09-2012, 07:52 PM

The underneath of Keyair's '84 is virtually identical to my '88.
Keyair's pictures are of the real emergency brake, pull the emergency brake handle you have emergency brake. Normal and logical ,right?
The dreaded E-Brake doesn't show up until the '90s, the E-Brake is applied by an extremely powerful spring and braking effort is helped by the shoe effect. OK sounds great right?
The problem is that the pressurized hydraulic system that releases and keeps the brake off until needed would fail unpredictably. The result would be a sudden and interesting experience at say 70mph? on a freeway. Followed by a vehicle locked in place until someone could slide under the coach who was strong enough to force back the spring. All in all a big step forward in braking technology. LOL.

LimeyRich · 10-18-2012, 09:23 AM

Parts are coming in nicely now! Last week the Transgo kit arrived, ARP header bolts came in from Summit, the shortened driveshaft was ready. New emergency brake cable arrived, and the new shift cable was shipped yesterday. I found that Nalley GMC in Brunswick, GA, has new transmission support cross members for the 4l80e in 91 thru 96 model years 14,800&15,600 GVW P30s! Ordered one, (as I cannot see any differences in the basic frame design since the eighties, sub-components look updated but not the actual frame) it will be in next week ($80.96 shipped). We will see if that helps the installation once it gets here ( fingers crossed for luck).
I will start taking pics, as I think my camera is ok.

bkahler · 10-18-2012, 10:31 AM

Quote:

Originally Posted by LimeyRich

Parts are coming in nicely now! Last week the Transgo kit arrived, ARP header bolts came in from Summit, the shortened driveshaft was ready. New emergency brake cable arrived, and the new shift cable was shipped yesterday. I found that Nalley GMC in Brunswick, GA, has new transmission support cross members for the 4l80e in 91 thru 96 model years 14,800&15,600 GVW P30s! Ordered one, (as I cannot see any differences in the basic frame design since the eighties, sub-components look updated but not the actual frame) it will be in next week ($80.96 shipped). We will see if that helps the installation once it gets here ( fingers crossed for luck).
I will start taking pics, as I think my camera is ok.

I am definitely looking forward to pictures of your installation. I'm even happier to hear you found a rear frame support that might work. $80 isn't bad and I would easily spend that much money in time and materials making one myself.

How much did it cost to have the drive shaft shortened?

Brad

LimeyRich · 10-18-2012, 10:52 AM

Are you sitting down? Including a new u-joint,
$89.00 !!!!! Fleet Pride did the work.
The last time I had a driveshaft modified (1980) it ran over $100. I was expecting around $180, this was a very pleasant surprise!
The part from Nalley is new also.
The pics will probably be late next week. It will be fit together time once the support arrives. I have decided to pull the 4L80 before buttoning everything up and do an HD rebuild with the beefing up Transgo mods.
I will be waiting for my buddies to help again, as even with the transmission jack I just cannot do it by myself. :-(
After this much work, better safe than sorry

bkahler · 10-18-2012, 02:38 PM

Quote:

Originally Posted by LimeyRich

Are you sitting down? Including a new u-joint,
$89.00 !!!!! Fleet Pride did the work.
The last time I had a driveshaft modified (1980) it ran over $100. I was expecting around $180, this was a very pleasant surprise!
The part from Nalley is new also.
The pics will probably be late next week. It will be fit together time once the support arrives. I have decided to pull the 4L80 before buttoning everything up and do an HD rebuild with the beefing up Transgo mods.
I will be waiting for my buddies to help again, as even with the transmission jack I just cannot do it by myself. :-(
After this much work, better safe than sorry

Heck that's not bad at all. I'm thinking about using one of the drive shafts from the 345 and have it shortened to fit. I haven't compared the u-joints between the Argosy and the 345 but I will most likely have to do something about the u-joint that connects to the differential but I figure a drive shaft shop should be able to deal with that.

I think the differential in the Argosy is a 14 bolt 10-1/2" unit but I don't know how that compares to what is in the 345. When I get home later this month I'll get the calipers out and do some measurements.

Brad

LimeyRich · 10-18-2012, 06:03 PM

I would stick with shortening the stock Argosy driveshaft myself.
For the following reasons.
Multi part driveshafts have to be balanced as an assembled unit, you are probably not taking enough material away to have to re-balance.
Your shortened driveshaft will be slightly shorter than it's present length. There is actually no advantage to a larger diameter driveshaft, unless you are making a longer shaft or adding LOTS of power.
If you change the diameter of the front shaft, you should change the rear shaft diameter too, but then the entire rotating assembly (front and rear shafts, u-joints) will need to be dynamically balanced.
If however you are doubling the torque and horsepower of the original Argosy engine, you are radically increasing the twisting torque applied to the shaft tubes, and then do by all means change up to the 345 shafts. It would be cheap insurance.
I have found driveshaft shop guys to usually be just of much of gearheads as me, they will usually give sound practical advice on just what their work will stand up to.
All the best.Cheers.
P.S. Have a pint for me, I can't have it anymore :-(

bkahler · 10-18-2012, 06:42 PM

Good information. I have high hopes that the Argosy is going to have more HP and higher torque than the factory 345. The cam is "COMP CAMS 11-203-3 HIGH ENERGY™, 260H GOOD TORQUE AND POWER, SMOOTH IDLE".

I'll have to measure the shafts on the 345 and then on the Argosy to see if what will fit where. The Argosy has a carrier bearing so that will have some impact on what drive shaft that I end up using.

I'm going to have to start looking around for a good drive shaft shop. Odds are I'll have to drive 45 miles to Somerset KY to find a good one.

Brad

ElCamino Man · 10-20-2012, 05:59 AM

Ill throw in a piece of advice here: since your 4L80Es are already sitting on the counter, Id use the money you saved and get a shift improver kit. They generally run $100 (for a TH350 at least, not sure on the 4L80E) and come with 2 sets. One for street driving, and the other for towing/hauling. Of course youd need the tow/haul one. Iv heard nothing but good fortune from these. They drastically improve the shifting on these old trannys

bkahler · 10-20-2012, 08:57 AM

Quote:

Originally Posted by ElCamino Man

Ill throw in a piece of advice here: since your 4L80Es are already sitting on the counter, Id use the money you saved and get a shift improver kit. They generally run $100 (for a TH350 at least, not sure on the 4L80E) and come with 2 sets. One for street driving, and the other for towing/hauling. Of course youd need the tow/haul one. Iv heard nothing but good fortune from these. They drastically improve the shifting on these old trannys

Isn't the Transgo kit the same as a shift improver kit?

ElCamino Man · 10-21-2012, 08:02 AM

It prolly is lol. Several people make them

LimeyRich · 10-22-2012, 10:18 AM

I have uploaded and attached the photos I have so far.They show the Transgo kit for correcting over and under pressure, increasing the liveability of the 4L80. The shortened driveshaft. My favorite air over hydraulic jack.
The parking brake. The Optishift head unit in a temporary spot. The Optishift wiring temporarily secured. The close /interference of the transmission shift mechanism.

bkahler · 10-22-2012, 02:42 PM

Thanks for the pictures!

Your brake drum sure looks to be a lot smaller than the brake drum on my 4L80E and the one on our 310. The Argosy has the parking brakes at the rear axle so I don't know if it will be an issue or not as I try to install it.

Thanks again and keep the pictures coming.

Brad

LimeyRich · 10-22-2012, 03:39 PM

It came out of a 1996 HD (3500?) 14,000/16,500 gvw series commercial box truck without the electric/hydraulic brake,that they put in the 90's motorhomes. However, the brake shoe is much wider than the original airstream shoe, swept area looks about the same. The big drawback from my point of view, it's a spring operated "normally on" system. So a quick learning curve in not driving off with the parking brake on.
The nice part is the trans' does have a parking pawl, so I don't have to spend the money on adding one.
New trans support should be here tomorrow P.M.
How did you make out with finding a rag joint?

bkahler · 10-23-2012, 07:43 AM

Quote:

Originally Posted by LimeyRich

It came out of a 1996 HD (3500?) 14,000/16,500 gvw series commercial box truck without the electric/hydraulic brake,that they put in the 90's motorhomes. However, the brake shoe is much wider than the original airstream shoe, swept area looks about the same. The big drawback from my point of view, it's a spring operated "normally on" system. So a quick learning curve in not driving off with the parking brake on.
The nice part is the trans' does have a parking pawl, so I don't have to spend the money on adding one.
New trans support should be here tomorrow P.M.

So that's what the electric parking brake looks like. First time I've seen one.

My 4L80E came out of about a 1992 Chevy box truck. Based on your statement above it sounds like mine may not have a parking pawl installed. Just how expensive is it to have one of those installed in the transmission?

Quote:

How did you make out with finding a rag joint?

I'm waiting until I get home to get measurements before trying to order one. I figured since I'm buying one for the Argosy I might as well buy one for the 310 since the steering in it is a little sloppy. I've replace all the joints, etc just never replaced the rag joint.

Brad

LimeyRich · 10-23-2012, 08:34 AM

Well Brad I still don't think we have seen an electric/hydraulic E brake! They have a whole lot of "unnecessary plumbing" and cabling in order to make the parking brake "secure" and "safe" for us feeble RVers!

.
I strongly advise going to:
www.irv2.com/forums/f22/auto-park-brake-workhorse-p-32-a-138863.htm

A good place to start learning why we do not want to accidentally upgrade our vintage machines to this awful conglomeration of machinery.

It is possible that your 4L80 has a traditional pull-on parking brake as it appears that some earlier models did not yet have the "Auto-Park" system. Unfortunately I do not have proof of this, only what I have tried to glean from other posters on forums.
It also appears that the drivers of midsize commercial trucks were deemed to be trusted to be able to put on a handbrake

.

The parking pawl is good news though

. Your 4l80 probably has it, if not. All the small parts for adding "Park" are readily available new or used, and most 4l80's come with them. They are easily installed by any transmission shop or mechanic who dabbles in transmissions.
See the second pic in Jakes 4L80 build sequence on the "Nasty Z28" forum. The rod that runs from the shift lever to the back of the transmission activates the small spring loaded "pawl" parts located in the back of the case, here:
> 4L80E Build - NastyZ28.com <

LimeyRich · 10-23-2012, 05:11 PM

Sorry that link to> iRV2 - The Friendly RV Forum Community < is not working properly. So go over to "irv2", "forums", then "The chassis club forums", "Workhorse" and peruse the "Auto Park threads"
All the best.